Voltage regulator with improved load regulation

摘要

A voltage regulator comprises a ground node, a pick-off node, a regulator branch, a load branch, and a current mirror the regulator branch and the load branch are connected in parallel between the pick-off node and the ground node; the load branch comprises one or more resistive connecting lines that are connectable in series with the load to generate a load current through the load branch; the regulator branch comprises a bias node, a resistive element, and a tap node; the bias node is arranged to provide a regulated bias voltage; the resistive element is connected between the bias node and the pick-off node; and the tap node is connected between the bias node and the resistive element. The current mirror is connected to the tap node and arranged to draw a mirror current from the tap node; the mirror current having a component that is proportional to the load current.

主权项

1. A voltage regulator for applying a regulated voltage across a load, wherein the voltage regulator comprises a ground node, a pick-off node, a regulator branch, a load branch, and a current mirror;
the ground node is arranged to provide a ground voltage; the pick-off node is arranged to provide a pick-off voltage; the regulator branch and the load branch are connected in parallel between the pick-off node and the ground node; the load branch comprises one or more resistive connecting lines that are connected or connectable in series with the load to generate a load current through the load branch; the regulator branch comprises a bias node, a first resistive element, a tap node, a voltage divider comprising second and third resistive elements, and a fourth resistive element, the voltage divider connected between the tap node and the ground, wherein the voltage divider comprises the bias node, the bias node is arranged to provide a regulated bias voltage, the first resistive element is connected between the bias node and the pick-off node, the second resistive element is connected between the voltage divider and the ground node, and the tap node is connected between the bias node and the first resistive element the first, second, third, and fourth resistive elements have resistances R1_met, R1, R2, and R2_met, respectively, and the ratio R1_met/R2_met is equal to the ratio R1/R2; wherein the current mirror is connected to the tap node and arranged to draw a tap current from the tap node; the tap current having a component that is proportional to the load current so that the pick-off voltage increases when the load current increases and decreases when the load current decreases.